Tapping performance and underlying wrist muscle activity of non-drummers, drummers, and the world's fastest drummer.
ABSTRACT Studies of rapid unimanual tapping have assumed that the human rate limit for voluntary rhythmic movement is 5-7 Hz, which corresponds to an inter-tap interval (ITI) of 150-200ms. In fact, the winner of a recent contest to find the world's fastest drummer (WFD) can perform such movements using a handheld drumstick at 10 Hz, which corresponds to an ITI of 100 ms. Because the contest measured only the number of taps by the WFD, we examined the stability of the ITI and the underlying wrist muscle activity of the WFD. By comparing the performance and wrist muscle activity of the WFD with those of two control groups (non-drummers (NDs) and ordinary skilled drummers (ODs)), we found that the WFD had a relatively stable ITI and more pronounced reciprocal wrist muscle activity during the 10-Hz performance. Our result indicates that very fast, stable tapping performance can be achieved by keeping the wrist joint compliant rather than stiff.
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ABSTRACT: The strength of time-dependent correlations known as stride interval (SI) dynamics has been proposed as an indicator of neurologically healthy gait. Most recently, it has been hypothesized that these dynamics may be necessary for gait efficiency although the supporting evidence to date is scant. The current study examines over-ground SI dynamics, and their relationship with the cost of walking and physical activity levels in neurologically healthy children aged nine to 15 years. Twenty participants completed a single experimental session consisting of three phases: 10 minutes resting, 15 minutes walking and 10 minutes recovery. The scaling exponent (α) was used to characterize SI dynamics while net energy cost was measured using a portable metabolic cart, and physical activity levels were determined based on a 7-day recall questionnaire. No significant linear relationships were found between α and the net energy cost measures (r<0.07; p>0.25) or between α and physical activity levels (r=0.01, p=0.62). However, there was a marked reduction in the variance of α as activity levels increased. Over-ground stride dynamics do not appear to directly reflect energy conservation of gait in neurologically healthy youth. However, the reduction in the variance of α with increasing physical activity suggests a potential exercise-moderated convergence towards a level of stride interval persistence for able-bodied youth reported in the literature. This latter finding warrants further investigation.Pediatric exercise science 04/2014; · 1.61 Impact Factor
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ABSTRACT: Motor execution processing has been examined using an index of behavioral performance such as reaction times, kinetics, and kinematics. However, difficulties have been associated with the study of motor inhibitory processing because of the absence of actual behavioral performance. Therefore, non-invasive neurophysiological and neuroimaging methods including electroencephalography, magnetoencephalography, transcranial magnetic stimulation, and functional magnetic resonance imaging have been used to investigate neural processes in the central nervous system. We mainly reviewed research on somato-motor inhibitory processing based on data obtained by using these techniques, which can examine 'when', 'where, and 'how' motor inhibition occurs in the brain. Although to date a number of studies have used these techniques separately, few studies have utilized them in a comprehensive manner. In this review, we provide evidence that combining neurophysiological and neuroimaging methods should contribute to our understanding of how executive and inhibitory functions are implemented.The Journal of Physiological Sciences 05/2014; 64(4). · 1.25 Impact Factor
Neuroscience Letters 459 (2009) 69–73
Contents lists available at ScienceDirect
journal homepage: www.elsevier.com/locate/neulet
Tapping performance and underlying wrist muscle activity of non-drummers,
drummers, and the world’s fastest drummer
Shinya Fujiia,b,c,∗, Kazutoshi Kudob, Tatsuyuki Ohtsukib, Shingo Odaa
aLaboratory of Human Motor Control, Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
bDepartment of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba 3-8-1, Japan
cJapan Society for the Promotion of Science, Chiyoda-ku, Tokyo 102-8472, Japan
a r t i c l e i n f o
Received 23 March 2009
Received in revised form 25 April 2009
Accepted 27 April 2009
a b s t r a c t
Studies of rapid unimanual tapping have assumed that the human rate limit for voluntary rhythmic
movement is 5–7Hz, which corresponds to an inter-tap interval (ITI) of 150–200ms. In fact, the winner
of a recent contest to find the world’s fastest drummer (WFD) can perform such movements using a
handheld drumstick at 10Hz, which corresponds to an ITI of 100ms. Because the contest measured only
the number of taps by the WFD, we examined the stability of the ITI and the underlying wrist muscle
activity of the WFD. By comparing the performance and wrist muscle activity of the WFD with those
of two control groups (non-drummers (NDs) and ordinary skilled drummers (ODs)), we found that the
WFD had a relatively stable ITI and more pronounced reciprocal wrist muscle activity during the 10-Hz
performance. Our result indicates that very fast, stable tapping performance can be achieved by keeping
the wrist joint compliant rather than stiff.
© 2009 Elsevier Ireland Ltd. All rights reserved.
To assess manual motor function, studies of human motor con-
trol have used a simple motor task called the “rapid tapping task,”
in which participants are asked to tap as fast as possible for sev-
eral dozen seconds using finger , wrist [3,11], elbow, and/or
shoulder movement [13,29]. These studies have found that the
rate limit at which the motor effectors of the finger and wrist
can move voluntarily is 5–7Hz, which corresponds to an inter-
tap interval (ITI) of 150–200ms (see also the review ). Several
studies have investigated the effect of practice on the rate limit of
rapid tapping by training participants for several weeks or months
[14,15,25] or comparing the performances of musical instrument
players (i.e., pianists, string players, and drummers) with those of
non-players [2,8,9,12]. These studies reported that the rate limit
was still within the 5–7Hz limit.
In fact, the winner of a recent international contest to find
the world’s fastest drummer (WFD) can perform such movements
using a handheld drumstick at 10Hz, which corresponds to an ITI
of 100ms. Specifically, the WFD performed a record 1247 taps in
60s with alternate left- and right-handed drumming movements,
which approximately equals 10Hz movement with each hand over
∗Corresponding author at: Laboratory of Human Motor Control, Graduate School
of Human and Environmental Studies, Kyoto University, Yoshida-nihonmatsu-cho,
Sakyo-ku, Kyoto 606-8501, Japan. Tel.: +81 75 753 6876; fax: +81 75 753 6876.
E-mail address: firstname.lastname@example.org (S. Fujii).
of taps within a certain length of time, the stability of the ITI and
underlying muscle activity of the WFD remain unknown.
Previous studies of human motor learning showed that motor
performance becomes stable during the acquisition of a skill,
whereas the level of muscle co-contraction gradually decreases
[10,23]. In our recent study examining the wrist muscle activity
of the preferred right hand during rapid unimanual drumming
, we also showed that drummers had a lower level of muscle
co-contraction (i.e., clearer reciprocal contraction of antagonistic
muscle groups) and a more stable ITI compared to non-drummers.
pronounced reciprocal activity of the wrist muscles and have a sta-
Another possibility exists, however, concerning the muscle
small involuntary oscillating movements, such as those observed
while maintaining a posture), it has been argued that the human
nervous system can produce rapid oscillatory movements of a
body part, including 10Hz movement [6,19]. PT is believed to
originate from multiple factors, including the oscillatory activ-
ity of the central nervous system, motor unit firing properties,
mechanical resonances, and reflex loop resonance [6,19]. Although
the amplitude of the PT is usually too small (e.g., ∼0.097mm in
the index finger of young adults ) to use for rapid drumming
movement, several studies have shown that it can be increased
(but becomes more variable) by increasing limb stiffness through
0304-3940/$ – see front matter © 2009 Elsevier Ireland Ltd. All rights reserved.
S. Fujii et al. / Neuroscience Letters 459 (2009) 69–73
WFD employs a PT through increased limb stiffness, we hypothe-
sized that the WFD would show increased muscle co-contraction
and a variable ITI.
This study tested whether the WFD shows (i) pronounced recip-
rocal muscle activity and a stable ITI or (ii) increased muscle
rate, variability of the ITI, and wrist muscle activity of the WFD and
compared them with those of two control groups: non-drummers
(NDs) and ordinary skilled drummers (ODs).
The WFD is a 44-year-old man who began drum training at 3
years of age and has 41 years of drumming experience. His handed-
strongly right-handed). He is a professional drummer who plays all
styles of music and won an international contest to find the world’s
fastest drummer in 2005. All the NDs (n=23, 17 men and 6 women)
and ODs (n=44, 37 men and 7 women) were right-handed. The
handedness scores assessed using the Edinburgh Inventory were
89.6±18.7 (mean±standard deviation) and 89.1±16.7 for the NDs
and ODs, respectively. The mean ages of the NDs and ODs were
25.3±7.2 and 30.1±10.5 years old, respectively. Participants in the
ND group had no drum training experience, whereas the OD group
included professional drummers and students from a special music
school. The ODs began drum training at 16.7±4.9 years of age and
had 12.8±11.4 years of experience. Typically, the ODs played rock,
popular, or jazz music.
In accordance with the Declaration of Helsinki, the partici-
and provided written informed consent before participating in the
study. The experimental procedure was approved by the Ethics
Committee of the Graduate School of Arts and Sciences of the Uni-
versity of Tokyo.
The drum throne was adjusted to provide a comfortable height
and position for each participant. The participants sat on it while
holding a drumstick in one hand with the palm down. The partic-
ipants were asked to use the drumstick to hit a drum practice pad
(6in. in diameter, VIC-PAD6S, Pearl), under which a strain gauge
flexion/extension movements. The participants were asked to tap
participants were instructed to tap with the drumstick, using each
hand separately (i.e., unimanual approach) as fast as possible for
12s. The left- and right-hand tasks were repeated three times each.
The order of the left- and right-hand tasks was randomized. Before
the experimental measurement, the participants were allowed to
practice until they felt accustomed to performing the task.
The electromyogram (EMG) was recorded for 8 NDs (5 men and
3 women, 28.5±10.7 years old) and 10 ODs (9 men and 1 woman,
29.3±9.4 years old, who began drum training at 15.2±4.6 years
trol groups. As in our previous study , surface EMG electrodes
(Ag–AgCl, 8mm diameter) were attached to the flexor carpi ulnaris
and extensor carpi radialis. We focused on wrist muscle activity
for high frequency movements in their routine drum playing. We
also confirmed that during the experiment, all of the participants
mainly used the wrist joint to perform the drumming task.
The signals from the force transducer and EMG were amplified
(SA-100D; TEAC), converted from analog to digital at a frequency
of 1000Hz, and recorded on a computer. The data from 12s of
slowing period by omitting data collected during the first 1.5s and
last 0.5s, thereby analyzing only the data collected during the mid-
dle 10s. The signal of the force transducer (first rows in Fig. 1A)
enabled the detection of tap time . The interval between two
sequential taps was defined as the ITI. We calculated the mean tap-
ping rate and within-trial standard deviation (S.D.) of the ITI over
Unfortunately, we could not obtain right-hand EMG data for
the WFD due to difficulties with the apparatus during the lim-
ited time available. Therefore, only the left-hand EMG data for
the WFD were analyzed and compared to those of the NDs and
ODs. As in our previous study , the left-hand EMG time series
were full-wave rectified and smoothed using a moving average
of 9ms per window width (see the second and third rows in
Fig. 1A). To compare the wrist flexor and extensor muscle activi-
ties, cross-correlations between the moving-averaged EMG signals
of the flexor and extensor muscles were calculated . The signal
from the wrist extensors was shifted with respect to the wrist flex-
ors within the range of 0ms to the duration of the mean ITI for each
coefficient and the time lag at the moment for each participant.
The higher the value of the cross-correlation coefficient was, the
more pronounced was the reciprocal activity of the wrist flexor and
The values of each dependent variable were averaged over the
trials for each participant. For the mean tapping rate and the S.D.
of the ITI, the asymmetry score was calculated using the following
asymmetry score =R − L
R + L× 100,
where R and L denote the performances of the right and left
hands, respectively. The mean tapping rates of the NDs and ODs
(ANOVA) because the data met the prerequisites for conducting
parametric analyses (the Kolmogorov–Smirnov test for a normal
distribution and the Levene test for homogeneity of variances).
The performing hand (left or right) was the within-participant
variable, and drumming experience (non-drummer or drummer)
was the between-groups variable. When a significant interaction
was observed, between-group differences were analyzed using
the unpaired t-test, and within-group differences were analyzed
using paired t-tests. Regarding the S.D. of the ITI for the NDs
and ODs, the between-group differences were analyzed using the
Mann–Whitney U-test, and within-group differences were ana-
lyzed using the Wilcoxon matched-pairs signed-ranks test. The
cross-correlation coefficient and the time lag for the NDs and ODs
were subjected to unpaired t-tests. Statistical tests were deemed
significant at an ˛ level of 0.05. When conducting multiple com-
parisons, the ˛ level was adjusted using the Bonferroni procedure
to compensate for the increased probability of finding significant
The mean tapping rates for the left and right hands of the NDs
were 6.2±0.8 and 7.0±0.9Hz, respectively, and those of the ODs
were 6.4±0.6 and 6.8±0.6Hz, respectively (see Fig. 2A). The two-
difference was observed for either the left (t65=−1.31, ns) or right
(t65=0.76, ns) hands. The mean tapping rate of the left hand was
lower than that of the right hand for both the NDs (t22=4.26,
p<0.01) and ODs (t43=4.98, p<0.01). However, the asymmetry
score of the mean tapping rate for the ODs (2.86±3.86) was signifi-
pared to the NDs. The WFD had a mean tapping rate of 10.2 and
10.0Hz for the left and right hand, respectively (see Fig. 2A). The
mean tapping rate for the left and right hands of the WFD was the
highest among the participants. The asymmetry score of the WFD
was −1.15 (i.e., an almost symmetrical tapping speed).
S. Fujii et al. / Neuroscience Letters 459 (2009) 69–73
Fig. 1. Typical examples of the tap force and EMG signals in a non-drummer (left), an ordinary drummer (middle), and the world’s fastest drummer (right). (A) Typical signals
for 500ms. The vertical dashed lines indicate the tap time detected from the signal of the tap force (first rows). The second and third rows of graphs show the rectified and
smoothed EMG signals of the wrist flexors and extensors, respectively. (B) Ensemble average of the smoothed EMG signals with reference to the tap time. Gray areas indicate
the within-participant standard deviation of muscle activity.
The S.D. of the ITI for the ODs was much smaller than that for
the NDs for both the left (z=−5.94, p<0.001) and right (z=−5.27,
p<0.001) hands (see Fig. 2B). The S.D. of the ITI of the right hand
was significantly smaller than that of the left hand for both the NDs
(z=−3.07, p<0.01) and the ODs (z=−3.89, p<0.001); however, the
ODs had significantly lower asymmetry scores than did the NDs
(−13.16±19.04 vs. −25.13±24.79, z=−2.42, p<0.05). The left- and
right-hand S.D. of the ITI for the WFD was 9.5 and 6.6ms, respec-
tively. The value of the WFD was similar to that of the ODs. The
asymmetry score of the WFD was −17.70. When we calculated the
coefficient of variation (CV) of the ITI, the statistical results were
consistent with the S.D. of the ITI. The left- and right-hand CV of
the ITI for the NDs was 24.0±12.0 and 18.0±12.7%, respectively,
those for the ODs were 7.0±5.7 and 5.1±3.2%, respectively, and
those for the WFD were 9.6 and 6.6%, respectively.
Fig. 1B shows the typical ensemble average of the moving aver-
age signals in reference to the tapping point in a ND, an OD, and the
WFD. The ensemble averages demonstrate that the WFD had rela-
tively less muscle co-contraction with smaller within-participant
variability compared to the ND and OD. The time lag between
the wrist flexors and extensors of the NDs, ODs, and WFD were
nificant difference was found in the time lag between the NDs and
ODs (t16=−0.72, ns). The time lag of the WFD was the shortest
observed among the participants. The peak value of the cross-
0.51±0.16, and 0.70, respectively (see Fig. 3B). No significant dif-
ference was found in the cross-correlation coefficient between the
NDs and ODs (t16=−0.62, ns). The cross-correlation coefficient of
the WFD was the highest among the participants, showing that the
reciprocal muscle activity was most pronounced in the WFD.
rocal muscle activity and a stable ITI or (ii) increased muscle
WFD showed pronounced reciprocal activity of the wrist muscles
that the WFD kept his wrist joint compliant, rather than stiff, while
drumming at 10Hz.
We postulate two functional reasons why the WFD showed
pronounced reciprocal muscle activation rather than increased
muscle co-contraction. First, a lower level of muscle co-contraction
or higher coherence between antagonistic muscle groups would
be physiologically more efficient and prevent muscle fatigue
[16,23,27]. Second, using the PT through increased muscle co-
contraction inevitably results in more variable movements .
This would not be suitable for drum playing, as producing a regular
an important element in musical performance.
Nevertheless, it is still possible that the WFD utilizes the neural
substrate of the PT, given that Carignan et al.  recently showed
that the PT amplitude can be modulated voluntarily without using
muscle co-contraction. They showed that the PT amplitude of the
postural index finger was successfully modulated not by using the
co-contraction of finger muscles, but through strategies such as
concentration, relaxation, visualization, and control of breathing.
From these observations, they indicated that cortical influence is
S. Fujii et al. / Neuroscience Letters 459 (2009) 69–73
non-drummers (NDs), ordinary drummers (ODs), and the world’s fastest drummer
(WFD). The error bars indicate the standard deviation between participants (n=23
standard deviation (S.D.) of the inter-tap interval (ITI).
Fig. 3. Myoelectric variables of non-drummers (NDs, white bars), ordinary drum-
mers (ODs, gray bars), and the world’s fastest drummer (WFD, black bars). The error
bars indicate the standard deviation (S.D.) (n=8 for the NDs, n=10 for the ODs).
(A) Time lag between the wrist flexors and extensors at the peak cross-correlation
coefficient and (B) peak value of the cross-correlation coefficient.
being exerted on the PT without muscle co-contraction. In addi-
tion, recent brain imaging studies have revealed changes in the
activity of the cortical motor areas associated with tapping prac-
tice [14,15] and with asymmetry of tapping skill . In view of
these studies, it might be possible that the WFD achieved 10-Hz
rhythmic movement by utilizing the neural substrate of the PT
through cortical modulation that was not accompanied by wrist
Is the achievement of 10-Hz performance and the pronounced
reciprocal muscle activity of the WFD related to the early age at
which he began drumming (i.e., 3 years old) or to his 41 years of
drumming experience? To address this question, we examined the
correlation of the performance and myoelectric variables with the
age of initiation of drumming and years of drum training expe-
rience among the drummers (i.e., ODs and WFD). For the years of
no significant correlation with any variable (|r|=∼0.28, ns), indicat-
ing that the 41 years of drumming practice was not directly related
to the extraordinary performance of the WFD. Because the WFD
stated that he had specifically practiced to improve his tapping rate
to win the contest and to achieve impressive drumming perfor-
but the amount of deliberate practice (i.e., concentrated practice
especially designed to improve specific aspects of an individual’s
performance)  was related to his 10-Hz performance.
Regarding the age of commencement of drum training, sig-
nificant correlations were found between age of onset and the
left-hand mean tapping rate (r=−0.31, p<0.05) and the S.D. of the
ITI (r=−0.34, p<0.05). That is, the earlier participants started drum
training, the more rapid and stable the performance of the non-
preferred left hand was. Therefore, the early initiation of drum
training by the WFD might be related to his non-preferred left-
suggesting that the early hand skill training of musicians interacts
with the cortical organization of hand motor dominance [1,28]. In
the future, an investigation of the brain structure or function of the
WFD will provide further insight into the neural substrates that
allow voluntary control of 10-Hz rhythmic movements.
We thank Mr. H. Tsunoda and the Wild Music School (Tokyo,
Japan) for their support in running this experiment. This study was
supported by a grant for the fellows of the Japan Society for the
Promotion of Science (JSPS) awarded to S. Fujii, a Grant-in-Aid for
Scientific Research (Nos. 17500416 and 21300215) from the JSPS
awarded to K. Kudo, and a Grant-in-Aid for Scientific Research (B)
(No. 19300216) awarded to T. Ohtsuki.
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